The present invention relates to pipe or tubular good handling apparatus. More particular, the invention relates to an apparatus for picking up tubular goods and transferring the picked up goods to the floor of a derrick, and for receiving tubular goods from the derrick and stacking or laying down the received goods.
Numerous different types of apparatus are previously known for picking up and laying down tubular goods involved in a drilling operation. Examples of such goods include drill tubing, casing, drill collars and drill pipe. For the purposes of convenience, such tubular goods will hereinafter be referred to as "pipe". It will be appreciated, however, that the present invention can be used to move any type of equipment used with a drilling operation.
Previously known drill pipe handling apparatus are described in U.S. Pat. No. 3,785,506, entitled "Drill Pipe Handling Apparatus" and U.S. Pat. No. 3,810,553, entitled "Pipe Handling Device". Both of these patents describe track-type machines for picking up and laying down pipe. The machines include a lifting device for lifting pipe from a rack and depositing the lifted pipe in an elevated trough. A pair of dollies are positioned in the trough for receiving a pipe deposited in the trough and for transferring the received pipe, through an inclined chute, to the floor of a derrick. The trough used with the devices is rotatable about a horizontal axis to transfer pipe received from the derrick, through the inclined chute, to a device for lowering the pipe onto a pipe rack. A brake is mounted on the inclined chute to control the rate of descent of pipe through the inclined chute during a pipe lay down operation.
Several problems have been encountered with pick up and lay down devices of the type described in the aforementioned patents. For instance, the devices are usually positioned on a cat walk of a derrick and greatly interfere with personnel access to the derrick. Also, assembly and disassembly operations are required when the apparatus is shifted from laying down pipe to picking up and vice versa. For instance, the brake on the inclined chute interferes with feeding of pipe through the chute during a picking up operation. Thus, the brake must be removed. Also, the lifting devices must be removed before the lowering devices can be used.
Other types of pipe handling apparatus are described in U.S. Pat. No. 3,713,547, entitled "Endless Cable Way for Transporting Pipe"; U.S. Pat. No. 3,825,129, entitled "Pipe Handling Apparatus"; and U.S. Pat. No. Re. 28,071, entitled "Portable Type Handling Apparatus". These patents describe wire line machines for picking up and laying down pipe. The machines use a system of cables and pulleys to raise and lower pipe sections.